• 자원환경지질
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• 제29권5호
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• pp.545-559
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• 1996

Rare metal (Nb-Zr-REE) ore deposits are located in the Chungju area. Geotectonically, the rare metal ore deposits are situated in the transitional zone between Kyeonggi massif and Okcheon belt. The rare metal deposits are distributed in Kyemyeongsan Formation which consist of schist and alkaline igneous rocks. Alkali granite has suffered extensive post-magmatic metasomatism and hydrothermal processes. The ore contains mainly Ce-La, Ta-Nb, Y, Y-Nd, Nd-Th group minerals. More than 15 RE and REE minerals are found in the ore deposits. Allanite, one of the Ce-La rich REE minerals belonging to the epidote group, is the most common mineral in the studied area. The allanite- bearing rocks may be devided into seven types by features of occurrence and mineral associations; zircon type (ZT), allanite-vein type (AT), feldspar type (KT), fluorite type (FT), quartz-mica type (QT), iron-oxide type (MT), and amphibole type (HT). The allanite veins (AT) and zircon rich rocks (ZT) contain the highest total REE contents. Differences in REE abundance can be interpreted in terms of varying portions of magmatic hydrothermal fluid. Petrographical and chemical data are presented for allanites which were collected from different types. The allanites show wide variations in optical properties, due in part to differences in their chemical composition (depending on the types) and to the degree of crystallinity of the individual specimens. Allanite metamicts in biotite are generally surrounded by well developed pleochroic haloes. Usually, allanite is accompanied by zircon and other REE-bearing minerals. CaO and total REE contents $({\sum}RE_2O_3)$ range from 9.29 to 18.79% and 11.66 to 26.31%, respectively. Also, SiO, (28.87~32.61%), $Al_2O_3$ (8.30~16.88%), and $Fc_2O_3$ (16.74~24.38%) contents show varying contents from type to type. The ${\sum}RE_2O_3$ of allanite has positive relationships with $Fe_2O_3$ and negative relaton with CaO, $SiO_2$, and $Al_2O_3$ Backscattered electron microscope images (BEl) of allanite shows that the its mineral composition and texture is very complex. The allanite-bearing hosts show distinct light REE enrichment with strong negative Eu anomaly except for HI. The HT has an almost flat REE distribution pattern with a small negative Eu anomaly. The chemical variation of the allanites with occurrences and mineral association can be related to condition of temperature and oxidation states in precipitation environment.

• 대한화학회지
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• 제34권1호
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• pp.69-75
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• 1990

모자나이트 광물 중에 포함된 각각 희토류 원소를 이온회합 크로마토그래피 방법으로 분리 및 정량하였다. 정량하기 전에 양이온교환수지(Dowex 5OW-X8) 칼럼으로 희토류 원소를 집단 분리하였다. 이 때 수지 칼럼에 의하여 희토류 원소가 정량적으로 회수되며, 시료 중의 공존이온으로부터 깨끗이 분리됨을 방사성 추적자 및 유도쌍 결합 분광-질량분석법(ICP-MS)으로 각각 확인 하였다. 역상 칼럼($\mu$-Bondapak $C_{18}$)에 의하여 미량(ppm)의 희토류 원소를 pH 4.6의 $\alpha$-hydroxyisobutyric acid으로 0.05M부터 0.3M까지 기울기 용출하여 각각 분리하였다. 희토류 원소와 PAR (4-(2-pyridylazo)-resorcinol monosodium salt)과의 포스터 칼럼 착색반응을 통하여 각각의 희토류 원소를 검출하였다.

• 생약학회지
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• 제7권1호
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• pp.35-40
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• 1976

The plant distributions in the Na-Ree Dong in Dagelet Island and Baik-Rok Dam in Cheju Island were investigated and 143 genera, 187 species of plants were found in the Na-Ree Dong in Dagelet Island during 15 years from 1961 to 1975. From 1957 to 1975, 113 genera, 174 species of plants were found in Baik-Rok Dam in Cheju Island.

• Bulletin of the Korean Chemical Society
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• 제3권3호
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• pp.83-88
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• 1982

Viscosity and zeta-potential of 11.0 wt. % aqueous bentonite suspension containing various electrolytes and hydrogen-ion concentration were measured by using a Couette type automatic rotational viscometer and Zeta Meter, respectively. The effects of pH and elcctrolytes on the rheological properties of the suspension were investigated. A system, which has a large zeta-potcntial, has a small intrinsic relaxation time ${\beta}$ and a small intrinsic shear modulus $1/{\alpha}$ in the Ree-Eyring generalized viscosity equation, i.e., such a system has a small viscosity value, since ${\eta}={\beta}/{\alpha}$. In general, a stable suspension system has large zeta-potential. The stability condition of clay-water suspension can be estimated by viscometric method since stable suspension generally has small viscosity. The correlation between the stability, viscosity and zeta-potential has been explained by the Ree-Eyring theory of viscous flow.

• Nutritional Sciences
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• 제6권1호
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• pp.42-47
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• 2003

The objective of this study was to examine how circulating leptin concentrations and resting energy expenditures (REE) are related to body composition in obese adults, and to examine differences in these parameters according to gender. Twenty-three subjects, 6 males and 17 females, were recruited from patients with a body mass index (BMI) of greater than 27 at the Obesity Clinic of the K University Hospital. Anthropometric assessments and biochemical analyses were performed, and REEs were measured. In spite of having similar BMI values the plasma leptin levels of females (20.0$\pm$6.5 ng/ml) were significantly higher (p<.05) than those of males (14.2$\pm$6.1) ng/ml). In females, plasma leptin concentrations were found to be positively related to body weight. BMI, waist-hip ratio (WHR), fat mass (FM), body fat, and to the circumferences of forearm, waist and hip (p<.0001). However, in males, plasma leptin concentrations were positively related only to suprailiac thickness (p<.05). The higher plasma leptin levels in females compared to males may, at least partially. be explained by the females' higher subcutaneous fat mass. Plasma leptin concentrations appeared to reflect not only total fat mass but also regional fat distribution, especially in females. REE values of males (2254.3$\pm$256.2 kcal/day) were significantly higher (p＜.01) than those of females (1799.1$\pm$454.7 kcal/day). REE values for females were positively related to body weight, BMI, lean body mass (LBM), FM, body fat, and to the circumferences of waist and hip (p<.05); however, REE values for males were (positively) related only to LBM (p<.05). REE values were not related to plasma leptin concentrations for either males or females, indicating that the plasma level of leptin might not be a predictor for REE value.

• Nutritional Sciences
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• 제5권4호
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• pp.221-227
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• 2002

The objective of this study was to examine the effects of a weight loss program on the degree of obesity and levels of resting energy expenditure (REE) in overweight subjects according to their mitochondrial uncoupling protein 2 (UCP 2) genotype. Twenty-three subjects with a body mass index (BMI) greater than 27 were recruited from the Obesity Clinic of the Kyung-Hee University Hospital during the period of December 2000 - August 2001. The subjects were genotyped for the exon 8 allele; 15 subjects were found to be of del/del genotype, 8 were del/ins, and none were of ins/ins genotype. No significant association was found between the different UCP 2 genotypes and the initial levels of weight, fat mass (FM), lean body mess (LBM), BMI, REE, and REE/LBM ratio. After 12 weeks of a weight loss program, body weight and FM were significantly decreased, while LBM, total body water (TBW), and REE were not changed, irrespective of UCP 2 genotype. Initial fasting plasma levels of albumin, glucose, triglyceride, lipoprotein cholesterol, insulin, free triiodo-thyronine (T3), free fatty acid (FFA), and leptin were not different according to the UCP 2 genotype; furthermore, these blood parameters were not changed after the 12-week weight loss program. However, plasma levels of leptin decreased in both the del/del and ins/del genotypes, from 18.7 ng/ml to 13.4 ng/ml (p<.05), and from 18.1 ng/ml to 13.9 ng/ml (p＜.05), respectively, after the weight loss program. In conclusion, this study found no significant association between the del/del or del/ins UCP 2 genotypes and differing levels of REE or differing degrees of obesity, either before or after a weight loss program. This study provided evidence that a well- managed weight loss program could maintain levels of REE, which plays an important role in the maintenance of energy balance.

• 자원환경지질
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• 제34권4호
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• pp.319-328
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• 2001

연구지역의 철-희토류광상은 선캄브리아기의 편마암류내에 맥상으로 배태되어 있으며, 크게 두 개의 광체, 즉 자은광체(북부광체)와 홍천광체(남부광체)로 나뉜다. 광상에서 산출되는 경제적인 광물로는 자철석, 모나자이트, 스트론티아나이트 및 중정석이다. 산출광물의 공생관계 및 조직을 근거로 본다면, 광화작용은 카보나타이트의 분화작용과 관련되어 Na-카보나타이트 단계와 Fe-카보나타이트 단계로 나눌 수 있다. 주된 희토류광물은 Fe-카보나타이트 시기 동안에 침전되었다. 이처럼 철-희유광물이 카보나타이트와 관련되어 침전되었다고 고찰하는 증거로는 1) 스트론티아나이트와 모나자이트가 용리조직을 갖으며 산출되는 점, 2) 스토론티아나이트와 중정석이 용리조직을 갖는점, 3) 희토류광물이 주로 산출되는 지역에서 화성기원의 액마이트가 산출되는 점, 4) 탄산염광물-자철석-희토류광물의 공생 및 공존관계 등으로 볼 때 이 지역의 철-희토류광화작용은 화성기원의 카보나타이트에서 기원되었음을 암시하고 있다.

• Nutrition Research and Practice
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• 제12권4호
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• pp.283-290
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• 2018

BACKGROUND/OBJECTIVES: Indirect calorimetry is the gold-standard method for the measurement of resting energy expenditure. However, this method is time consuming, expensive, and requires highly trained personnel. To overcome these limitations, various predictive equations have been developed. The objective of this study was to assess the validity of predictive equations for resting energy expenditure (REE) in Korean non-obese adults. SUBJECTS/METHODS: The present study involved 109 participants (54 men and 55 women) aged between 20 and 64 years. The REE was measured by indirect calorimetry. Nineteen REE equations were evaluated for validity, by comparing predicted and measured REE results. Predictive equation accuracy was assessed by determining percent bias, root mean squared prediction error (RMSE), and percentage of accurate predictions. RESULTS: The measured REE was significantly higher in men than in women (P < 0.001), but the difference was not significant after adjusting for body weight (P > 0.05). The equation developed in this study had an accuracy rate of 71%, a bias of 0%, and an RMSE of 155 kcal/day. Among published equations, the $FAO_{weight}$ equation gave the highest accuracy rate (70%), along with a bias of -4.4% and an RMSE of 184 kcal/day. CONCLUSIONS: The newly developed equation provided the best accuracy in predicting REE for Korean non-obese adults. Among the previously published equations, the $FAO_{weight}$ equation showed the highest overall accuracy. Regardless, at an individual level, the equations could lead to inaccuracies in a considerable number of subjects.

• Journal of Trauma and Injury
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• 제34권1호
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• pp.13-20
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• 2021

Purpose: Nutritional therapy in the intensive care unit is an essential factor for patient progress. The purpose of this study was to compare resting energy expenditure (REE) calculated by prediction equations (PEs) to the REE measured by indirect calorimetry (IC) in trauma patients. Methods: Patients admitted to the trauma intensive care unit who received mechanical ventilation between January and December 2015 were enrolled. REE was measured by IC (CCM Express, MGC Diagnostics) and calculated by the following PEs: Harris-Benedict, Fleisch, Robertson and Reid, Ireton-Jones, and the maximum value (25 kcal/kg/day) of the European Society for Clinical Nutrition and Metabolism (ESPEN). All patients were ventilated at a fraction of inspired oxygen (FiO2) below 60%. Results: Of the 31 patients included in this study, 24 (77.4%) were men and seven (22.6%) were women. The mean age of the patients was 49.7±13.2 years, their mean weight was 68.1±9.6 kg, and their mean Injury Severity Score was 26.1±11.3. The mean respiratory quotient on IC was 0.93±0.19, and their mean FiO2 was 38.72%±6.97%. The mean REE measured by IC was 2,146±444.36 kcal/day, and the mean REE values calculated by the PEs were 1,509.39±205.34 kcal/day by the Harris and Benedict equation, 1,509.39±154.33 kcal/day by the Fleisch equation, and 1,443.39±159.61 kcal/day by the Robertson and Reid equation. The Ireton-Jones equation yielded a higher value (2,278.90±202.35 kcal/day), which was not significantly different from the value measured using IC (p=0.53). The ESPEN maximum value (1,704.03±449.36 kcal/day) was lower, but this difference was likewise not significant (p=0.127). Conclusions: The REE measured by IC was somewhat higher than that calculated using PEs. Further studies are needed to determine the proper nutritional support for trauma patients.

• Tuberculosis and Respiratory Diseases
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• 제44권5호
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• pp.1019-1029
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• 1997

연구배경 : 폐암 환자에서 체중감소와 영양결핍은 흔히 동반되며 체중감소가 있는 폐암 환자는 체중감소가 없는 환자보다 항암제 치료에 대한 반응이 좋지 않으며 예후도 나쁘다. 폐암환자에서의 체중감소는 안정시 에너지 소비(resting energy expenditure : REE)와 관계가 있다. 저자들은 폐암 환자에서 안정시 에너지 소비자 증가된 빈도를 알아보고 안정시 에너지 소비에 영향을 주는 인자를 알아보고자 하였다. 방 법 : 처음 진단된 31명의 폐암 환자를 대상을 안정시 에너지 소비를 측정하여 대조군과 비교하였다. 안정시 에너지 소비량은 ventilated hood system을 사용하여 간접 칼로리측정법(indirect calorimetry)으로 측정하였다. 안정시 에너지 소비량은 칼로리측정기로 측정한 산소 소모량과 이산화탄소 생성량을 이용하여 Weir공식으로 계산하였으며 안정시 에너지 소비량의 예측치는 Harris-Benedict공식으로 구하여 비교하였다. 결 과 : 안정시 에너지 소비량은 폐암 환자와 대조군에서 각각 $1415.5{\pm}237.0$(Kcal/day), $1253.6{\pm}174.6$(Kcal/day)로 폐암 환자에서 유의하게 더 높았으며 REE 백분율도 각각 $116.8{\pm}15.8$(%), $100.7{\pm}13.8$(%)로 폐암 환자에서 유의하게 더 높았다. REE백분율은 흡연, 주 증상의 기간, 폐기능 장애 정도, 무기폐유무, 폐암의 위치 등에 의한 차이는 없었으나 원격전이 유무에 따라서는 원격전이가 있었던 군과 없었던 군에서 각각 $127.0{\pm}17.3$(%), $113.8{\pm}11.6$(%)로 원격전이가 있었던 군에서 유의하게 더 높았다. 폐암 환자중에서 과대사 상태와 정상대사 상태사이에 흡연, 주 증상의 기간, 원발암의 용적, 원발암의 기관지 내시경상의 위치, 무기폐나 기관폐색의 유무, 폐암의 병기, 원격적인 유무에 따른 차이는 없었다. 결 론 : 폐암 환자에서 안정시 에너지 소비가 비교적 높은 빈도로 증가되어 있었으며 증가된 안정시 에너지 소비는 폐암의 원격천이 유무와 관계가 있었다.